1. Field
Embodiments to an image forming apparatus having a developing unit, an intermediate transfer body, and a transfer roller.
2. Description of the Related Art
In an image forming apparatus having a developing unit, an intermediate transfer body, and a transfer roller, a transfer roller is used to transfer toner transferred to the intermediate transfer body to a printing medium. That is, when a printing medium passes through a gap between the intermediate transfer body and the transfer roller, the transfer roller transfers the toner transferred to the intermediate transfer body to the printing medium. The transfer roller contacts the intermediate transfer body, forming a nip. A separate test pattern is transferred to the intermediate transfer body to conduct color registration or adjustment of color tone. Some of the toner used to form the test pattern often remains on the intermediate transfer body even after removing of the toner is performed.
While no printing medium enters the gap between the intermediate transfer body and the transfer roller, the toner remaining in the test pattern forming area of the intermediate transfer body may contaminate the transfer roller. The contaminated transfer roller may in turn contaminate the rear surfaces of subsequent printing media entering the space between the intermediate transfer body and the transfer roller to allow printing thereon.